The importance of peritoneal cytology in endometrial carcinoma.

From 1971-1986, peritoneal washings were obtained for cytologic examination at the time of primary exploratory laparotomy in 340 patients with endometrial adenocarcinoma. Seventy-two samples (21.2%) contained malignant cells. The finding of malignant cytology increased with stage of disease: stage I, 17%; stage II, 19.5%; stage III, 68.7%; and stage IV, 85.7% (P less than .001). In 248 patients with clinical stage I disease for whom uterine evaluation was complete, there was an increasing incidence of malignant cytology with increasing grade (P = .002), depth of myometrial invasion (P = .003), and adnexal spread (P less than .001). Twelve of 41 patients (29.3%) with clinical stage I and positive cytology developed recurrent disease, compared with six of 207 (2.9%) with negative cytology (P less than .001). Survival for all stages together was poorer in patients with positive washings than in those with negative washings (P less than .001). This difference in survival was also observed in patients with clinical stage I disease (P less than .001). Among patients with surgical stage I disease, disease-free survival was also superior in the group with negative cytology. In both clinical and surgical stage I, intra-abdominal recurrences were more common among patients with malignant peritoneal cytology.